New single channel capacitive controller is compact, robust and cost-effective

07-07-2014

Press picture (Hi-Res)

Precision sensor manufacturer Micro-Epsilon has launched a new compact, robust capacitive displacement controller that provides a combination of technical advantages and high performance at an affordable price.

The new capaNCDT 6110 controller is suitable for measuring displacement, distance and position in a diverse range of applications, from test cells to on-vehicle testing, mobile applications and highly automated production environments. In addition, due to its low cost, compact design and high performance, the controller is particularly suitable for high volume OEM applications. Here, the capaNCDT 6110 can be used as a base specification for modification to user-specific requirements.

Robust and simple to use, the capaNCDT 6110 is compatible with all capaNCDT series capacitive sensors from Micro-Epsilon. The measurement system comprises a capacitive displacement sensor, sensor cable, controller (electronics) and a supply/signal output cable. With all items available from stock, the user can quickly select the most suitable sensor range and cable length to be used with the capaNCDT 6110 electronics. The system offers high temperature stability (200ppm), maximum linearity of 0.1µm and maximum resolution of 0.005µm. Measurement output values are selectable 0-10V or +/-5V DC. Seven measuring ranges are available from 0.2mm up to 10mm.

Chris Jones, Managing Director at Micro-Epsilon UK comments: “Due to its compact, robust design and flexible 24V [9-36V] DC power supply, the capaNCDT 6110 is ideal for mobile applications, on-vehicle (passenger cars and trucks) applications, as well as integration in industrial plant and machines. The measurement system is suitable for use with all electrically conductive materials and offers nanometre repeatability and high temperature stability.”

Capacitive measurement explained

Capacitive displacement measurement is one of the highest precision methods of non-contact displacement measurement. With the capacitive principle, sensor and target operate like an ideal parallel plate capacitor. The two plate electrodes are formed by the sensor and the opposing target. If an AC current with constant frequency flows through the sensor capacitor, the amplitude of the AC voltage on the sensor is proportional to the distance between the capacitor electrodes. An adjustable compensating voltage is simultaneously generated in the amplifier electronics. After demodulation of both AC voltages, the difference is amplified and output as an analogue signal.

Because the sensor is constructed like a guard ring capacitor, almost ideal linearity and resolution against metal targets is achieved. The technology also offers high temperature stability, as changes in the conductivity of the target have no effect on the measurement. Capacitive sensors can also measure insulators.

The technology is sensitive to changes in the dielectric sensor gap and so operates most effectively in clean, dry applications. Cable length is also relatively short due to the effect of cable capacitance on the oscillating circuit tuning.

The capacitive measuring principle enables the rapid replacement of a sensor in just a few seconds. This simplified replacement of sensors with different measuring ranges and the interchangeability of capaNCDT controllers can be carried out without any re-calibration required. A typical sensor replacement takes around 5 seconds, unlike conventional systems that have to be subjected to time-consuming calibration and linearisation.

For more information on the capaNCDT 6110, please call the Micro-Epsilon sales department on 0151 355 6070 or email info@micro-epsilon.co.uk